The invention relates to a radio communications system according to the preamble of claim 1, a base station for it and a control means connected thereto, a wireless subscriber terminal for it and a method of radio transmission according to one of the independent claims.
A wireless subscriber terminal with a transceiver which transmits radio signals by various radio transmission modes to base stations and receives radio signals therefrom is known from U.S. Pat. No. 5,590,397. A first system which operates according to a first radio transmission mode, in particular according to a mobile radio standard for public cellular radio, forms a first part of the base stations. A second system which operates according to a second, different radio transmission mode, in particular according to a radio standard for private cordless telecommunication, forms a second part of the base stations. Each system has a broadcast channel via which a system identification code is transmitted. The broadcast channels have to be scanned by the subscriber terminal. A priority list in which the system identification codes of the systems are listed in a preferred sequence is stored in the wireless subscriber terminal, and the subscriber terminal selects the best system identification code from the received system identification codes with the aid of the priority list. It therefore selects the best radio transmission mode for the subscriber terminal. Therefore a radio communications system with at least one base station and with at least one wireless subscriber terminal which contains a transceiver in order to transmit and receive radio signals by at least two different radio transmission modes and which contains a selector in order to select one of the various radio transmission modes at least prior to a subscriber connection being established with one of the, at least one, base stations, is known from U.S. Pat. No. 5,590,397. The known radio communications system and method of radio transmission have the disadvantage, however, that a bottleneck can occur in the radio coverage if a large number of subscriber terminals have similar priority lists and, as a result, select the same radio transmission mode to establish subscriber connections at the same time. Consequently, only one of the two systems would be loaded for the most part. In addition, the providers who provide their radio services via the various systems must recognise the various system identification codes and store them in the subscriber profiles.